arXiv subjects

Akbota Senkebayeva

Publications and source records attributed to Akbota Senkebayeva.

3 recordsLinked to original sources

arXiv2026

Correct mathematical models of joint filtration of two immiscible viscous liquids

Mathematical models of joint filtration of liquids are the main part of mathematical models of oil displacement by suspension. Since mining is a very important and urgent economic task, exact modeling of joint filtration of two different fluids is also an urgent economic task. For example, mathematical models of oil displacement by suspension are needed to create a hydrodynamic simulator of oil by suspension. All the existing simulators are based on the macroscopic Buckley-Leverett model, which does not distinguish between the free boundary separating liquids and the details of liquid interaction. All these fundamental processes occur at a microscopic level corresponding to the average size of pores, while all proposed macroscopic models operate on completely different orders of magnitude and do not distinguish between free boundaries or the characteristics of fluid interactions and are simply a set of axioms. Exact modeling involves describing the process using the equations of classical Newtonian continuum mechanics at the microscopic level (average size of tens of micrometers). The only obstacle to using such models is that any numerical implementation for domains hundreds of meters in size would take years. A solution to this problem (the homogenization method) was proposed in the works of J. Keller and E. Sánchez-Palencia.

math.AP↗

arXiv2026

Correctness of Biot's model of in situ leaching for incompressible liquid and compressible solid components

We study a mathematical model of in situ leaching of rare metals, in which the joint filtration of two liquids is governed by the microscopic model $\mathbb{A}^{\varepsilon}$. A key difficulty is the unknown (free) boundary $Γ(r)$ between solid and liquid components, determined by an additional condition on $Γ(r)$; no standard methods exist for this nonlinear problem. To resolve it, we apply the fixed point theorem. For a given function $r(\boldsymbol{x},t)$ from a set $\mathfrak{M}_{(0,T)}$ of sufficiently smooth functions describing the skeleton structure, we consider the auxiliary problem $\mathbb{B}^{\varepsilon}(r)$: an elliptic system for displacements of the liquid and solid components coupled with parabolic equations for the acid concentration. Selecting the weak solution of minimal smoothness, we apply the homogenization method to pass from the microscopic to the macroscopic description. The resulting macroscopic model $\mathbb{H}(r)$ contains a homogenized boundary condition that expresses the normal boundary velocity $V_{N}=\partial r/\partial t$ as a linear function of the acid concentration $c$. Since $c$ depends on $r$ via an operator $\mathbb{F}\colon\mathfrak{M}_{(0,T)}\to\mathfrak{M}_{(0,T)}$, we prove that $\mathbb{F}$ is Lipschitz continuous and, by Banach's theorem, possesses a unique fixed point $r^{*}$, which yields the unique solution $\mathbb{H}=\mathbb{H}(r^{*})$.

math.AP↗

arXiv2026

Mathematical Models of Traffic Flow at a Signalized Intersection

This paper presents two one-dimensional mathematical models describing automobile traffic flow on straight road segments at a signalized intersection. When the traffic light is permissive, the flow density and velocity are obtained by solving an initial-boundary value problem for a first-order hyperbolic system. When the signal is prohibitive, the same quantities are governed by a mixed system comprising a second-order parabolic equation for the velocity and a first-order equation for the density.

math.AP↗